WL-N/WLG
86
Operation Procedures
Operation
• Carefully determine the position and shape of the dog or cam so
that the actuator will not abruptly snap back, thus causing shock.
In order to operate the Limit Switch at a comparatively high speed,
use a dog or cam that keeps the Limit Switch turned ON for a
sufficient time so that the relay or valve will be sufficiently
energized.
• The method of operation, the shape of the cam or dog, the
operating frequency, and the travel after operation have a large
influence on the durability and operating accuracy of the Limit
Switch. The cam or dog must be smooth in shape.
• Appropriate force must be imposed on the actuator by the cam or
dog in both rotary operation and linear operation. If the dog
touches the lever as shown below, the operating position will not
be stable.
• Unbalanced force must not be imposed on the actuator. Otherwise,
wear and tear on the actuator may result.
• With a roller actuator, the dog must touch the actuator at a right
angle. The actuator or shaft may deform or break if the dog touches
the actuator (roller) at an oblique angle.
• Mount so that the actuator travel after operation (OT) is not
exceeded. If the travel after operation (OT) exceeds the limit,
switch failure could result. When mounting the Limit Switch, be
sure to adjust the Limit Switch carefully while considering the
whole movement of the actuator.
• The Limit Switch may soon malfunction if the OT is excessive.
Therefore, adjustments and careful consideration of the position of
the Limit Switch and the expected OT of the operating body are
necessary when mounting the Limit Switch.
• When using a pin-plunger actuator, make sure that the stroke of
the actuator and the movement of the dog are located along a
single straight line.
Others
• If the Switch will be left in a location outside the storage
environment conditions, if condensation has formed, or after long-
term storage exceeding one year, at the minimum, check the
operating characteristics, contact resistance, insulation resistance,
and dielectric strength, and conduct a check under the operating
conditions.
• If using normal open (NO), be sure to fully press in the actuator. The
proper press-in depth is 70 to 100% of rated OT.
• Conduct periodic inspection on a regular schedule.
Incorrect
Correct
Snapped
back
Abruptly
actuated
Incorrect
Correct
Snapped
back Abruptly
actuated
Incorrect
Dog
Dog
Correct
Incorrect
Correct
Roller
Roller
Dog
Dog
Correct
Incorrect
Dog
Dog
Operating
body
Install a stopper.
PT (Pretravel)
FP (Free position)
OP (Operating position)
OT (Overtravel)
TTP (Total travel position)
Reference line
70% of
rated OT
100% of
rated OT
Distance to the
optimum setting range.
Optimum setting range
Correct
Stopper
Incorrect
Correct
Operating
body
Operating
body
